If the voltage is set any higher than its
maximum limit the generator may be
damaged.
CAUTION!
Further adjustments are possible with the AVR TERM
software.
6.4.5 Wiring diagrams for different circuits
In the appendix of this manual there are diagrams for con-
nections other than the factory star-series connection
(standard unless otherwise specified on order).
6.4.6 Initial start-up
Before starting up the generating set check that all exter-
nal connections are in order and that the protections are
in place.
During the initial start-up pay particular attention for any
unusual noise that might signal an incorrect alignment be-
tween engine and generator.
Do not touch the generator while in operation
and immediatly after the generating set has
stopped, since certain parts may still be very
WARNING!
hot.
Generators are rotating electrical machines that involve
potentially hazardous live or moving parts, therefore the
following is strictly prohibited:
• an improper use;
• removal of covers and disconnection of safeties.
Due to these inherent hazards, all works of electrical or me-
chanical nature must be carried out by qualified specialists.
The lack of routine check-ups and poor
maintenance can cause severe damage to
persons and/or objects.
WARNING!
7. AFTERSALES ASSISTANCE AND MAIN-
TENANCE
The maintenance and fault diagnostic
procedures involve risks that may cause
severe injury or even death. These
WARNING!
procedures should therefore be carried out
solely by qualified electrical and mechanical
specialists. Before any maintenance and
cleaning work make sure that there are no live
parts, that the generator housing has cooled
to ambient temperature, that the generating
set cannot be accidentally started up and
that all procedures are strictly observed.
7.1 Control and check procedures
7.1.1 Control of windings and electrical insulation
The condition of the windings can be checked by measuring
their electrical resistance to earth. While running this test
disconnect the voltage regulator and EMC filter. It is usually
sufficient to control the main winding.
The readings should give a measurement of at least
2MOhm. If the insulation resistance is below this threshold,
the alternator alone should be oven dried at 80 ÷ 100°C
for 6 hours. Before carrying out this operation remove the
voltage regulator.
7.1.2 Control of the rotating rectifier diodes
This check can be performed with a multimeter, the knob
must be selected to the position "Diode test". The lead of
each diode (1) has to be removed from the connections
with the rotor exciter (see figure), but it's not necessary
to removed them from the alluminium plate (2) where they
are fixed.
The faulty diode will have high (theoretically infinite)
resistance in both directions (open diode) or it can have low
resistance on both directions (diode in short) by placing
the tips on both directions. Meanwhile the correct working
diode will have low resistance in forward direction and high
(theoretically infinite) in the other (reverse) direction.
7.1.3 Control of the surge suppressor
This element (surge suppressor 3, see above figure), that
is connected between two terminals of rectifier bridge,
is meant to suppress high voltage peaks on the main
rotor winding and save rectifiers diodes from damaging.
Normally, if good, this element will have high (infinite)
resistance in both directions. When damaged, in most
cases it can be noticed by visual inspection.
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